When a HEAD request is issued for a file under /content/dam, then instead of returning the correct headers back, it issues a 302 redirect to the same file with "/" appended to the end of the URL.  For example, this HTTP request:

HEAD https://www.geometrixx.com/content/dam/test.jpg HTTP/1.1

Responds with a 302 redirect to:

https://www.geometrixx.com/content/dam/test.jpg/

Cause

This is a known product bug CQ-4221520.

Resolution

The fix is included in AEM 6.4.

Cumulative Fix Packs (CFPs) for older AEM versions:

• AEM 6.1 - A fix is available since 6.1SP2 CFP11
• AEM 6.2 - A fix would be made available in a future CFP
• AEM 6.3 - A fix would be made available in a future CFP